A330 GWCG on ECAM
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Join Date: Apr 2002
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A330 GWCG on ECAM
How does it calculate it's GWCG on the ground before take off? I know it get's its GW from the ZFW and BLOCK fuel which is entered into the FMGEC.
Is it worked out by the THS setting from the load sheet?
Am I correct in assuming that it recalculates it dynamically in the air by using the alpha vanes?
Is it worked out by the THS setting from the load sheet?
Am I correct in assuming that it recalculates it dynamically in the air by using the alpha vanes?
Join Date: Dec 2004
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FCMC GW and GWCG rely upon ZFW and ZFWCG entries in INIT B. Fuel quantity is measured by FCMC.
For the calculation itself, I assume it (FCMCs) compute it as you would do on a manual LTS. No THS involved for that computation.
FE GW and GWCG calculations are a bit more detailed in FCOM 1.22.40p4:
FE Weight computation (back up)
When the aircraft is below 14625 feet and 255 knots :
GW = f(alpha, CAS, N1/EPR actual, CG from FE part, altitude)
When the aircraft is above 14625 feet or 255 knots :
GW = TOGW - WFU
TOGW: takeoff gross weight
WFU: weight fuel used acquired from FADECs.
FE Center of gravity computation (back up/aft cg computation)
The CG is computed from the position of the horizontal stabilizer and is function of the N1/EPR, Vc, ALT, MACH and GW from FE part.
For the calculation itself, I assume it (FCMCs) compute it as you would do on a manual LTS. No THS involved for that computation.
FE GW and GWCG calculations are a bit more detailed in FCOM 1.22.40p4:
FE Weight computation (back up)
When the aircraft is below 14625 feet and 255 knots :
GW = f(alpha, CAS, N1/EPR actual, CG from FE part, altitude)
When the aircraft is above 14625 feet or 255 knots :
GW = TOGW - WFU
TOGW: takeoff gross weight
WFU: weight fuel used acquired from FADECs.
FE Center of gravity computation (back up/aft cg computation)
The CG is computed from the position of the horizontal stabilizer and is function of the N1/EPR, Vc, ALT, MACH and GW from FE part.
